my apologies, the code I gave for the hidden element to use on the confirm page:
<input name="UPS_Service" type="hidden" id="UPS_Service" value="<?php echo((isset($_GET["UPS_Service"]))?$_GET["UPS_Service"]:"") ?>" />
is not correct, it should be:
<input name="UPS_Service" type="hidden" id="UPS_Service" value="<?php echo((isset($_POST["UPS_Service"]))?$_POST["UPS_Service"]:"") ?>" />